Field of Invention
The present invention relates to a semiconductor technology, and more particularly to a conductive plug and a method of forming the same.
Description of Related Art
In a typical semiconductor device fabrication, conductive plugs such as vias or contacts are usually provided in a dielectric layer to connect the adjacent horizontal metal layers. As the level of integration of semiconductor devices is continuously increased, the aspect ratio (or height-to-width ratio) of the conductive plugs becomes higher. However, it is rather difficult to fill a metal layer in the high aspect ratio contact or via openings during the step of forming the conductive plugs. Voids are generally observed in the vias or contacts due to the poor metal gap filling property, and the reliability and performance of the device are accordingly affected.